Screeining apparatus.



J. w. PETTIBONE.

SCREENING APPARATUS.

APPEIGATIOH FILED MAR. S, 1913. 1 1 08,6 6 Patented Aug. 25, 1914,

lllllllllill THE NORRIS PETERS CO.. EHOTO-LITHOH WASHINGTON, D. C.

I B Z Q i M" m flQ i. a g 9 w 7 f 0 w E 6 J 6 6 um x M x ym 5 Y 5 lwmwwUNITED STAT Eg BEIGE.

JAMES XV. FETTlBONE, OEMTUSKEGON, MICHIGAN, ASSIGNOR TO PHILIP P.SCI-INOR- BACI-I, LOUIS E. SCI-INQRBAGTI, AND JAB/IE3 VET. PE'I'TIBONE,OF MUSKEGON, MICHI- GAN, COPARTNER'S DOING BUSIHESS S MACHINE COM?ANY.

SCREENING errnna'rus.

l,3l8,61l6.

Application filed Wfi'arch 8,

To all whom it may concern Be it known that 1, JAMES l V. Pn'rrnionn,citizen of the United States, residing at shegon, in the county ofMuslregon and fil-tzite o'l liilichigan, have invented certain new anduseful Improvements in Screening Apparatus, of which the following is aspec fication.

lvly invention relates to improvements in screening apiniratus andparticitilarly to that i'erni of screen which is adapted for use inconnection with mortar mixing machines.

tine oi? the objects of my invention is to provide a centrifu al screenin Which the larger lumps or masses are rejected and delirered throughan opening Whereas the screened material is positively dischargedthrough a separate opening.

Other objects of my invention are to provide a rugged, indestructible,centrifugal screen, ellicient in its operation and not liahle to get outof 0rd The machine ritremely simple, requiring practically no sl-Iill onthe part of the ope itor, and all of its moving parts are nnide strongand serviceable and cheap of construction and protected against flyingsand, grit, or stone.

ther objects of my invention and benefits of my machine will l'iocomereadily apparent to persons skilled in the art from a crmsideration oithe :tollouing description when taken in conjunction With the dra\vinns. whereinirigure 1 is a vertical, sectional view, thro gh myimproved screen, showing its application to a portable, concrete mixinghint; and Fig. 2 is a horizontal section In all the views the samereference characters are employed to indicate similar parts.

In the exemplification Which I have chosen for a clear disclosure of myinvention, I have illustrated the centrifugal screen as applied to aportable concrete mixer, the side sills of which are indicated by thenumerals 10 and 11. Bearing brackets l2 and 13 are secured to the sillsand have at their lower ends, bearing caps 16% and 15, carrying the axle16, upon the ends of which are mounted the traction Wheels 17 and 18.

Specification of Letters Patent.

Patented A11 25, 1914.

Serial No. 753,072.

.lt common practice in portable concrete mixing outfits to provide asource of o .ver, such as a gas engine, electric motor or the like, andin the construction illustra ed the numeral 29 indicates a longitudinalpower shalt driven by such a motor, connected through suitable clutchingmech anisms "with a beveled gear l8. A handle 59 is shown extending tothe left for operating the clutch mechanism.

The sand screening apparatus consists of a sand receiving hopper 5%,having slightly tapered side Walls and having a ClOWllVifUfClly taperingbottom The bottom contains a central axial opening 56, through which thesand is discharged onto the screen at. The vertical shaft, 58, supportedin "liGtS 59 and (30, which are properly seto the "frame of the mineroutfit, caron its upper end a spider 61, secured to by a set screw 62,or the like. The r is provided with a series of radial arms vvhich serveas agitators to prevent pacl-zing of the sand and to loosen it up sothat it will readily fall through the opening By this means, I amenabled to screen wet sand. and even frozen sand may be readilyscreened. Within a casing, providing a bottom wall (3:1: and asubstantially circular side wall 65, is a rotary screen 65, which issecured to the shaft (38 by means of SQC\\S 67 or the like. The screenmembers '6 consist preferably of a series of annular, concen ric rings,(38, 60, 7O, 71 and 2 spaced apart so as to provide openings therectneen, of such size or dimension as to pern 't the passage of sand orgravel that ma be des' 'l to be passed into the mixing hopper. Thosescreen rings gradually increase in diameter, so that the rear edge ofthe lower ring is substantially in the reit cal plane of the front edgeof the next succeeding ring thereabme, thereby to pro- 'ile an inclined.path, over the inner c0nfronting surfaces of the rings for the easypassage of gravel, stone, or other nia- ,ll too coarse or too large topass through the intervening screening spaces. To tacil itate themoren'ient of the stone or coarse gravel ll prefer to round oil or taperthe inner surfaces of the ring, as at 73, to pro vide a more gradualpath for the ascending stones or gravel. The beveled gear Wheel 48 is indriving relation with a similar gear wheel T l secured to the shaft 75.The transverse shaft 75 is supported on similar bearings SO and 81. thatare secured to transversely extending cross pieces such as 82, which inturn are connected to the side frame members 10 and 11. The outboardbearing ofv the shaft 75 carries beveled pinion S-Ll, secured thereto bya set screw 85, or other like means, and has intermeshing drivingrelation with a similar, but somewhat larger, gear wheel 86 which issecured to the shaft 68 by means of a set screw 87.

By the shaft and gear connections heretofore described, the screen isdriven by the engine at a rate of preferably about 225v to 250revolutions per minute which is sufli cient velocity to accomplish theobject desired.

The screen casing is-provided, near its upper edge, with a tangentiallydisposed spout outlet for the rejected stone and gravel and with asubstantially radial outlet 87 through which to deposit the sifted sandinto the mixing trough, 37.

The rings of the screens 68 to inclusive are cast integral with the hubwhich surrounds the shaft 58 and with radially extending angularscrapers 88, of which there may be any desired number, four being shownin the drawing. These scrapers are rectangular at their lower edges soas to correspond with the shape of the lower corner of the sandreceiving casing. The tangentially arranged discharge spout 90 ispositioned at a point on the periphery of the screen casing remote fromthe radial opening 87 communicating with the mixing trough 87.

In the operation of the device, when. the sand has been dumped into thehopper 54-. it will find its way down the incline 55 and through theopening 56. The agitator, consisting of a spider 63, which. is connectedto the rotating shaft 58 that serves to rotate the screen, will agitatethe sand, wet or frozen, and will cause it to drop through the inclinedwall 5 at the axis of the rotating screen. The centrifugal action willimmediately cause the fine particles of sand to pass through theintervening spaces between the annular rings 68 to 72 inclusive and thelarger portions of material or gravel, which cannot pass through thesespaces will gradually roll up the inclined surfaces of the rings, by theeffect of centrifugal force, and pass out of the tangential opening ordischarge spout 86. The sand having fallen on the floor of the casingcontaining the screen will be scraped by means of the rectangularrotating scrapers 88 toward the discharge openings 87, and thereby itwill be dumped into the mixing trough and mixed with the putty, ce-

ment, or like material, that may have been previously deposited in thetrough. The rotating screen 66 is made of relatively large, strongparts, that are designed to stand wear and abuse and will last for along time without material change.

It is of course apparent that many changes may be made in theconstruction of the screen, as by varying the intervening spaces betweenthe rings through which the sand passes, by operation of centrifugaleffect, imparted to it by the rotating screen for the purpose ofregulating or controlling the fineness of the sand to be deposited inthe mixing trough, and it is, of course, evident that changes may bemade in other parts of the specific structure illustrated and stillembody the general idea involved in this construction and covered by theappended claims.

While I have herein described in some .particularity a specificembodiment of my invention for the purpose of clear disclosure, it isevident that other changes than those mentioned may be made within thescope and intendment of the appende claims without departing from thespirit of my invention.

hat I claim is:

1. A screen of the character described comprising a vertically disposedshaft; a series of concentric rings spaced apart and graduallyincreasing in diameter as they approach the top portion of the screen,

thereby providing an inclined perforate wall; a plurality of angularlyformed scrapers comprislng integral parts of said rings, and an integralhub for attaching said frame to a vertically disposed shaft; a casing,surrounding said screen, having a discharge opening for the screenedmaterial near its bottom and a tangentially disposed opening near itstop for discharge of the rejected material. i

A screen of the character described, comprising a vertically disposedshaft; a series of concentric rings spaced apart and graduallyincreasing in diameter as they approach the top portion of the screen,thereby providing an inclined perforate wall; a plurality of angularlyformed scrapers comprising integral parts of said ring, a casing,surrounding said screen, having a discharge opening for the screenmaterial near its bottom and a tangentially disposed opening near itstop for discharge of the rejected material.

In testimony whereof I hereunto set my hand in the presence of twowitnesses.

JAMES WV. PETTTBONE. In the presence of PHILIP P. SCHNORBAGI-I, FRED L.Tnorr.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Eatents Washington, D. G.

